1 /* $NetBSD: floppy_2hc.c,v 1.5 2009/02/04 15:22:13 tsutsui Exp $ */ 2 3 /*- 4 * Copyright (c) 2004 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by UCHIYAMA Yasushi. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/types.h> 33 #include "common.h" 34 35 bool 36 blk_to_2hc_position(uint32_t logical_block_number, uint32_t *position, 37 int *count) 38 { 39 int sector, side, cylinder; 40 41 /* 42 * 2HC: MFM format 43 * 80 cylinders/disk 44 * 2 sides/disk 45 * 15 sectors/track 46 * 512 bytes/sector 47 */ 48 if (logical_block_number >= 2400) 49 return false; 50 51 cylinder = logical_block_number / (15 * 2); 52 side = logical_block_number - (cylinder * 15 * 2) > 14; 53 sector = logical_block_number - (side + cylinder * 2) * 15; 54 55 if (position) 56 *position = (cylinder << 16) | (side << 8) | (sector + 1); 57 if (count) 58 *count = 15 - sector; 59 60 return true; 61 } 62